goto10

Spark-Star++ for magnetic rotary position sensor/breakout. I had great success with a MLX90316, a generic 8-pin SOIC to DIP breakout board, and a couple of components along with the Arduino library here: http://interface.khm.de/index.php/lab/experiments/rotary-positionsensor-mlx90316/
The library and write up made this relatively easy to work with. The sensor is incredibly accurate.

I was experiencing the 45/25/165 18:85:85 / 0/0/0 0:0:0 issue as well. Turns out I had the wiring wrong (I’m a beginner). I’m using the Mega 2560 and I have it wired up as follows:
GND - GND
VCC - 3.3v
SQW - GND
CLK - 52
MISO - 50
MOSI - 51
SS - 8
battery is attached
It now works with both Sparkfun’s example and maniacbug’s library (which is awesome!).

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